ImageScience.with_image('source.jpg') {|image| image.resize(600,600) {|resized| resized.save('resized.jpg')}}
ImageScience.with_image('resized.jpg') {|image| image.resize(600,600) {|resized| resized.save('resized_again.jpg')}}

-rw-r--r--   1 trevor  trevor    44504 Mar  7 12:45 resized.jpg
-rw-r--r--   1 trevor  trevor    44499 Mar  7 12:46 resized_again.jpg
-rw-r--r--   1 trevor  trevor  3878922 Feb 22 16:00 source.jpg